Process for the extraction of glue from mineral-dressed or chrome-tanned leather.



- been first soaked in alh li.

UNITED STA E rrrrnnr ALBERT RUDULF WEISS, Jlt, ()l HILCUENBACU, (YrEltMANY.

PROCESS FOR THE EXTRACTION OF GLUE FROM MINERAL-DRESSED 0R GHEQME- TANNED LEATHER Application filed August 28, 1907.

Specification of Letters, Patent.

Patented March li', 3.903.

Serial No. 390,540.

To all whom it may concern:

Be it lcnown that l, ALr-mrr room VEISS, Jr., 21 subject of the King of Prussia, German l l mporor, rosiding' at llilohonlmoh, Province of \Vestpholm, Kingdom of Prussia, Germany, Dommstrusso liT, lnn'o invontod certain new and usol'ul lim'uovomonts in Processes or the Extraction ol ti uo l'rom Mineral. or Chrome Tanned Leather, of \\'lll(l1 the following is it full, clear, and oxuot doscri tion.

lVy'invent-ion relates to a now and improved process wherohy the glue is oxtrnotod lrom mineral drossod nntteriuls, t'or instunoo ohrome-tunned leather. tip to tho prosont. such loatheroould only he detannod h trouting it with acids, somotimos ul'tor lowing Al'tor dot'unuiug the glue could ho extroott-ul. l llztVU t'ouud however, that it was sullioiont' to trout mineral or chrome dressed leather with ullcnli, for

instance with limo, soda. or othor hnsio suhstanoes at a suitable tomporttturo. ltwzts then partly detanned or tlOUlllUlllQtl; ui'tor such treatment it was possihlo, to extract a part ol' the glue by simply hoilingiho lozithor with water. The quantity of gluooxtrnztedis muterially increased it the mineral drossod loot hor is treatedwitl tho base at temporuturos up to a 100 C. or more for instance at a lit) to 125 C. Further oxperimonts have shown, that leather is also dotannod (and that without destroying the gluo containod therein) at the higher temperature mentioned, it suits of alkali having alkaline qualities for iustnuoo soda or earth alkali are employed instead of tho caustic alkalies or the caustic oarth ul culies. The phosphoric salts have shown thomsolvos to be particularly eliica'cious. The proooss may be of course combined in such manner. that the leather is first treated with limo and when partly detnnned, hoilod with salts of alkaline qualities or ulltulino rosotion, that continue the (lGClU'OIIllItQ' ut highor tomptr atures, the hydroxids and tho ululino salts me be employed simultzmoously.

he following examples show my process in detail: la: Mineral dressed or ohromo tunuod le'atheris thoroughly mixodwith illllli ol' limo.

and thou loft to itself for -18 hours at the tomporuturo o1" 35 C: the suporlluous limo with tho liquid containing tho ohromo, is 'romovod by washing and tho mutoriul boiled down in the wo'll known mttnuor. to obtain tho g'luo.

ll): 'lho minorul or olu'omo drossotl leather is trontod with at solution containing of ouustit: lmrytn (ln'tlroxid ot' lrmrium) or onustit: strontiuv (h \'.droxid ol str ntium say) for l2 hours at 36 t Tho suportluous ouustio lmrytu or st rontin togothor with tho liquid rontzlinihg tho ohromo. is thon romovod by washing, and tho tnutorhtl thus dotunnod u'or'. od for tho purposo ol' isohtt my; tho glue.

lo: The trozumont is tho sum/o as in the ll), only that it l \'o iultiilltllttgj o quurtor nor-- cont. of hydroxid ol' potassium or sodium is usod instoud of the hut in or strontin.

ll: Minorul or ohromo tlrossod loother is iltttifll with u lyov oi ourth ul'nli or of the hydroxid ol u light motul at u 100 C. and thou boiled down for tiluo.

lll: ltuw mutoriztl or ohrom dressed louthor is thoroughly mixod with n'zttor and thou t'nlrium-mono-phosphato or another phosplmte ol ouloium zuldod thoroto. 'lfhe wholo isthon hoilod down u. tho toxnpotuturo of 11 lit) to lit)" t. for glue. The phosplmto out ho ulso rophuod by lino y or ooursoly ground raw honos. instead oi row lmnossoourod honos i (a hoot-s treated with urid may ho used.

What 1 claim as my invention and desire to soouro hy Lottors Potent is: i

l'rA proooss for extracting glue from minorul drossod and chrome tanned leather, oonsisting in troutin; tho louthor with oomhinetious of tho light motttls showing allurline qunlitios and thou hoiling it down for the purposo oi' isoloting tho gluo.

2A proooss for oxtruot-ing g'luo from.

minorul drossod and ohromo tunnod lou'ther, consisting in tt'l'tttlllg tho louthor with the hydroxids of tho light. metals and then hoiliny; it down for the purposo of isolating the gluo.

3. A proooss l'or oxtrrtoting gmo from 1 minolnl tlrossod and chrome tannod leather consisting in boiling! lontltol' with the ulliw line salts of the light metals at tem iel'atures l at tem femtures up to' 125 till the glue is up to 125 C. till the glueis isolated; isolatex 4. A- process for extracting lue from 4 1 l m mineral dressed and chrome tann d leather, ALBERT RDDOLX r consisting "in treating the leather with WVitnesses:

hydroxid of the light metals and then boil- JEAN GRUND, ing it with alkaline salts of the light metals CARL GRUND. 

